In recent years, there has been alarming evidence that the protective ozone layer of the earth is shrinking in thickness. The ozone layer is critical to the health of living organisms inhabiting the earth because the ozone layer filters out deadly ultra-violet rays, and other rays, emitted by the sun. Considerable evidence has been gathered to demonstrate that the damage that is occurring to the ozone layer is caused by a number of mankind generated free radicals and freon-type propellents which have been used in aerosol container spray systems for many years. These propellents are lighter than the atmosphere and rise to the elevation of the ozone layer. Chemical reactions then take place between the radicals and the ozone in the ozone layer thereby forming other compounds and complexes and diminishing the free ozone in the ozone layer. There has even been recent evidence to indicate that deadly holes have appeared in certain portions of the ozone layer, for example, over Antarctica. If this trend continues, then the health of mankind will be jeopardized.
Recently, industrialized nations of the world have agreed to an international moratorium on the use of substances which have been demonstrated to have a destructive effect on the ozone layer of the earth. In 1987, the United States enacted sunset-type legislation which will force companies which are manufacturing substances which are demonstrated to have a destructive effect on the ozone layer, to phase out production of such harmful substances over a specified number of years. One of the most ozone layer destructive family of substances being manufactured are chlorofluorocarbons and fluorocarbons (Freons), which are widely used as coolants in refrigeration systems, and as propellents in aerosol spray containers holding products such as hair spray, cleaning compounds, and the like.
Because of the mounting evidence that chlorofluorocarbon and fluorocarbon propellents, and similar type propellents, in aerosol contained spray systems, have an accumulative damaging effect on the ozone layer, it is critical to the long term health of living beings on the earth to develop alternative aerosol generating containers which do not rely upon ozone destroying propellents. As an alternative, many aerosol-type consumer products recently introduced on the market use a pump type aerosol spray generating system, rather than the volatile propellent contained in an aerosol container. However, such manually operated aerosol pump systems are not entirely satisfactory because they are incapable of generating a fine consistent spray similar to the type that is generated by an aerosol container employing a fluorocarbon propellent.
A number of patents have been granted in recent years for aerosol generating pump systems, and the like. These are useful as alternatives to volatile propellent aerosol generating systems. U.S. Pat. No. 3,993,069, for example, illustrates a pumping system which utilizes a natural rubber bladder which is inflated and thereby generates pumping action from the force created by the bladder in seeking to return to its original size and shape.
Clark, U.S. Pat. No. 3,961,725, discloses a bladder power system with a tube which extends down the center of the bladder, the tube serving to keep the bladder in consistent shape as the bladder is inflated. Clark does not disclose that an inner resilient tube and an outer resilient tube can act in concert to generate a cumulative pressure on the contained liquid.
Kain, U.S. Pat. No. 4,121,737, discloses a "hot water bottle" type of bladder. Such a bladder is wider in one direction than the other. Such a construction makes it difficult for the bladder to co-operate with a liner which has the same shape. Consistent pressures are not generated. Moreover, Kain at column 4, line 29, specifically states that the liner 32 can be flexible but preferably has "only limited elasticity." At column 4, line 44, Kain states that the principal purpose of the liner is to prevent contact between the product to be dispensed and the material of construction of the pressure unit.
Lee et al., U.S. Pat. No. 4,222,499, disclose an outer resilient tube 12, which generates dispensing power, and a liner 64 which is not elastic. Since liner 64 is not elastic, Lee et al. evidently were not aware of the fact that a resilient liner could be used in association with a resilient outer tube to generate cumulative power on the contained liquid. Lee et al. were not aware that the liner could serve any other purpose than a simple liner to separate the contained liquid from the outer tube.
Thompson, U.S. Pat. No. 4,446,991, discloses a bladder powered aerosol system, but the liner 62 is simply a coating. Thompson does not disclose a resilient liner which in concert with the outer tube generates cumulative dispensing pressure.